Boise Weather in September

What's the weather like in Boise (Idaho) in September 2024?

The climate in Boise during September can be summarized as mild and dry.

September is in the fall / autumn in Boise and is typically the 4th warmest month of the year. Daytime maximum temperatures average around a comfortable 25°C (77°F), whilst at night 8°C (47°F) is normal.

Boise weather averages (imperial / metric)
Daytime temperature 25.1°C 77.2°F
Nightly temperature 8.3°C 46.9°F
Average temperature 16.7°C 62.1°F
Daily sunshine 10.8 hrs
Avg rainfall 19 mm 0.7 ins
Rainy days 4 days
Sea temperature 14.5°C 58.2°F
Humidity 45%
Windspeed 13.7kph 9 mph

On average September is the 3rd driest month of the year in Boise with around 19mm 0.7 inches of rain making it a dry time to visit. This rainfall is typically spread over 4 days, although this may vary considerably.

On the flip side this corresponds to an average of 10.8 hours of sunshine per day.

September temperatures in Boise

Boise average temperature in September

September rainfall

Boise average rain in September

September hourly sunshine

Boise average rain in September

The data used in these monthly averages covers a period of over 100 years right up until last year. As such they are a valid prediction of what to expect for the weather in Boise in September 2024.